P-750 climb power settings?

[Perk]

Does anyone know what power settings are best to get this thing to actually climb more than 100 fpm above 10k?  I'm setting 90% NG and 1800 RPM, and I've tried both settings higher and lower.  As soon as the airplane (at around 6500lbs) gets above 9k I have to back the vertical speed off to a crawl.  Even at 2 or 300 fpm it can't maintain airspeed and just keeps slowing down and increasing AOA until it inevitably stalls.  This thing's a turboprop they fly in the Himalayas right? 

 

I'm guessing there's probably a more efficient power setting that will split the difference and get closer to the book climb values, but I'm not seeing a power settings table in the manual and I haven't run across a real world P-750 POH yet.  Anyone have any recommended power settings?

[Nick Cooper]

Hello,

I know very little about flying but these settings seem to be working:

Click on the image to enlarge

 

It took a while but without touching anything, it reached this dizzy height.

 

 

 

 

 

 

 

 

[wain71]

surely not another product without a full manual with tutorial? sorry but that really annoys me, all aircraft released should have a good set of instructions.....

[Nick Cooper]

Hello Wayne,

thanks for your comment, it does come with these:

 

 

and the User Guide can be read at Orbx Direct, without the need to buy the aircraft: LINK

 

I can think of a great many aircraft models that I have downloaded over the years that did not include

"a full manual with tutorial."

 

There is a bewildering amount of information in both this document: https://usermanual.wiki/Document/PacificAerospacePAC750XLPOH.2114406947/view

and on this web page:  PACIFIC AEROSPACE PAC 750XL OWNER'S MANUAL Pdf Download | ManualsLib

There is also real world advice here: PAC 750XL Skydiving Aircraft - DiverDriver.com

and how to jump out of it here: LINK

 

 

[wain71]

thanks for clearing that up Nick, maybe not this but some more complicated planes should come with a tutorial, I find it very bad when someone brings out an airliner and can't be bothered to give us a good example of how to fly it, especially if they call it a 'study' aircraft...

[Perk]

Out of curiosity what's the airplane loaded at there Nick? 

There's normally recommended power settings in the POH either as a table in the performance section or as recommended settings for phase of flight in the normal operations checklists.  The current manual recommends cruise at 85% NG and 1850 RPM (page 8 ) and the performance section lists takeoff power setting as 91.5% NG at 2006 RPM (page 20), but there's nothing for climb power settings.  There's a MAX power settings table (page 9) but those generally shouldn't be used for extended duration and they won't provide the most efficient climb anyway, just the best angle of climb.

 

I'm kind of splitting the difference between takeoff and cruise power settings for continuous climb which is where I'd expect the airplane to offer the best compromise between climb performance, turbine temps, and fuel burn, but I'm struggling to climb at all above 9k with full fuel and 80% cargo loaded (in CG and still almost 1000 lbs below MTOW... gotta give it to PAC this thing's got an amazing useful load).  I've tried hand flying and using the autopilot in vertical speed mode.  Almost wondering if I need to step climb it to prevent airspeed from bleeding off?

[Bullfox]

I note there is a mixture control.  These engines need to have the mixture leaned as they climb.  For a really well done sim you can hear the engine rpms vary as you lean the mixture. 

[Perk]

1 hour ago, Bullfox said:

I note there is a mixture control.  These engines need to have the mixture leaned as they climb.  For a really well done sim you can hear the engine rpms vary as you lean the mixture. 

It's not really a mixture, it's a fuel condition lever.  There are three settings - cuttoff, ground idle, and flight idle.  I believe it controls the amount of fuel going to the turbine at idle and not the fuel side of the fuel air mixture like in a reciprocating engine. 

[Perk]

Did some more testing... it seems to be HEAVILY CG variable.  With the plane loaded to 80% via the slider on the pre-flight menu, the CG is near the aft limit and I have climb issues.  If I manually shift some of the weight to forward stations so it's not so tail heavy it climbs much better even at the same weight.  That's completely realistic, with a tail heavy airplane you get a higher angle of attack for the same climb rate and more incidence drag.  I'd just expect it to not be quite so bad with the weight inside the CG limit. 

 

Kind of guessing the limits depicted in the MSFS menu aren't the actual airplane limits.  Nick I looked through those links you provided and can't find a weight and balance table for the real P-750 XSTL.  I'll try setting it up in Foreflight when I get home and see if they have the stations and envelope stored, but it'd be interesting to run a real weight and balance setting stations like the sim does and see if it's actually in CG limits.

 

In any event, just about any reasonable power setting works with the CG far enough forward...  85% NG and 1900 RPM seems pretty reasonable for fuel burn, ITT, and climb rate.

[Bullfox]

did not realize it was a turbine.

[John Heaton]

I just wish that if anyone who is responsible for this magnificent addition to our hangars - would make adjustments to the steering

by increasing the arc to at least the Taxiway/Runway Markings

 

I seem to spend more time on the grass than on the tarmac when turning

[Rob Abernathy]

""Kind of guessing the limits depicted in the MSFS menu aren't the actual airplane limits.""

 

100% agree with this Perk! I've always wondered just how accurate the menu for CG was to the actual aircraft.  My guess is that it may be close most of the time and not at all close in others.  In testing I've found the default CG settings after the initial install needed to be adjusted manually .  I'm going back to check mine and run the numbers you show for a climb.  They say it's about 12-13 minutes from brake release to sky dive jump altitude (13,500) in the PAC and can squeeze in about 6 turnarounds without refueling in a day.  Love this plane.  

 

Thanks for those links Nick.   Most informative for sure.

 

On another note is anyone having difficulty trimming for level flight without the AP?  I have an old Saitek Cyborg evo joy stick that I use.  I've assigned two buttons on it for up/down trim.  Maybe just too old?  Or maybe I'm just too old.    

[John Heaton]

1 hour ago, Rob Abernathy said:

 

 

On another note is anyone having difficulty trimming for level flight without the AP?  I have an old Saitek Cyborg evo joy stick that I use.  I've assigned two buttons on it for up/down trim.  Maybe just too old?  Or maybe I'm just too old.    

You are not alone - I have both trimming capability on both Honeycombe Alpha and Bravo and have little or no trouble

with other aircraft - but this one requires constant attention

 

I also find the left wing is always drooping to the port side - and by the time one can get to the trim in the roof the aircraft

can get away with you. - yes - one could set it on a controller - but the wing drop is excessive - just the opposite to the turning 

ability - I refer to above

[Aussieflyer38]

4 hours ago, John Heaton said:

I just wish that if anyone who is responsible for this magnificent addition to our hangars - would make adjustments to the steering

by increasing the arc to at least the Taxiway/Runway Markings

 

I seem to spend more time on the grass than on the tarmac when turning

 

Same here John

[Perk]

I'm lucky enough to have one of the old Saitek trim wheels (from before Logitech bought out Saitek and stopped making them), and I've got a rudder trim knob on my old PFC throttle quadrant.  I haven't noticed any particular issue getting the airplane in trim, but it does drift more than a lot of simulated airplanes (though less than the Pipers I fly in real life).  Wondering if that's due to the fuel system, which seems to preference draining the rear left tank faster than the other tanks.
 

16 hours ago, John Heaton said:

I seem to spend more time on the grass than on the tarmac when turning

It's a PAC, it can handle a little grass    It does kind of feel like they modeled more ground friction than a lot of MSFS airplanes... wondering if they're using a trick like Ant's Tiger Moth does where the brakes are always applied a few percentage points.  I can still get it to pivot around the main gear, but it takes a lot of toe brake and a lot of throttle and I frequently find myself giving it too much gas.

Edited October 29, 2022 by Perk

[wolfko]

On 10/28/2022 at 4:58 PM, wain71 said:

thanks for clearing that up Nick, maybe not this but some more complicated planes should come with a tutorial, I find it very bad when someone brings out an airliner and can't be bothered to give us a good example of how to fly it, especially if they call it a 'study' aircraft...

 

The more they are using discord for support instead of a proper forum. Discord is fine for many things, but not for support and product info.

Edited October 30, 2022 by wolfko

[wain71]

On 10/30/2022 at 11:33 AM, wolfko said:

 

The more they are using discord for support instead of a proper forum. Discord is fine for many things, but not for support and product info.

I personally can't be bothered with discord, not everyone wants to go there, should do at minimum a ticket system, that usually works...

[John Heaton]

On 10/30/2022 at 9:33 PM, wolfko said:

 

The more they are using discord for support instead of a proper forum. Discord is fine for many things, but not for support and product info.

Looks like we have gone off topic - but here goes my 2c worth

 

Strangely - It took me a while to use Discord - and I actually only use it for a particular aircraft - in this case the Cessna 414AW - and the Honda 720 Jet etc.

and I find it extremely useful in that at the very least - 99% of the partakers actually use the aircraft and pass on so many details on operation aids

 

Yes! - It may be used by some as a support aid - but at least - one gets an answer - pronto without building a ticket - and in my discord visits -

the developeris just about always there - it's like a permanent Beta

 

The one only other time I use discord - when Orbx use it as a marketing tool to draw one's attention to a new product - which is becoming a pain-

and not used - as I'm sure - in the way I just described - and we use this forum instead - or set up a ticket - which the rest of us never see the answer

Edited November 1, 2022 by John Heaton

[Nick Cooper]

Hello,

everyone has their own preference, Discord can be very useful and it is what you want it to be, but

in essence, it is just a means of communication.

For the record, Orbx do not use it for formal customer support, but of course, just like these forums, peer to peer

support can be just as valuable and occasionally, Orbx staff may contribute as well.

[Rob Abernathy]

Back on topic, last night I checked and changed the loadout on the PAC and was able to make a climb to 13,500 in almost exactly 13 minutes at a steady 1,000'/minute climb rate.  Did have to adjust the prop rpm a little and the airspeed did slow to 90 kts near the top but overall I was pretty happy with it.